Larvae

 A larva is a distinct juvenile form large number of animals undergo before metamorphosis into adults. Animals with indirect development like insects, amphibians typically have larval phase of their life cycle.The larva's appearance is usually very different from the adult form (e.g. caterpillars and butterflies) including different unique structures and organs that don't occur within the adult form. Their diet can also be considerably different.Larvae are frequently adapted to environments break away adults. For example, some larvae like tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living during a distinct environment, larvae could also be given shelter from predators and reduce competition for resources with the adult population. Animals within the larval stage will consume food to fuel their transition into the adult form. In some species like barnacles, adults are immobile but their larvae are mobile, and use their mobile larval form to distribute themselves.Some larvae are hooked in to adults to feed them. In many eusocial Hymenoptera species, the larvae are fed by female workers. In Ropalidia marginata  the males also are capable of feeding larvae but they're much less efficient, spending longer and getting less food to the larvae.